Modern Steam Engines

water vapour

Similar to hydrogen-powered vehicles, the "exhaust" produced by nanoFlowcell electric vehicles is water vapour. But are the water vapour emissions from future electric vehicles environmentally friendly?

Critics of electric mobility are increasingly calling into doubt the environmental compatibility and sustainability of alternative energies. For many, automotive electric drives are a mediocre compromise of zero-emissions driving and environmentally harmful technology. Conventional lithium-ion or metal-hydride batteries are neither sustainable nor environmentally compatible - not in production, not in use and not in recycling, even if the advertising suggests clean "e-mobility".

nanoFlowcell Holdings is likewise often asked about the sustainability and environmental compatibility of nanoFlowcell technology and the bi-ION electrolytes. Both the nanoFlowcell itself and the bi-ION electrolyte solutions necessary to power it are produced in an environmentally compatible manner from sustainable raw materials. In operation, too, nanoFlowcell technology is completely non-toxic and in no way harmful to health. bi-ION, which consists of a slightly saline aqueous solution (organic and mineral salts dissolved in water) and the actual energy carriers (electrolytes), is likewise environmentally friendly in use and recycling.

QUANTiNO in city traffic

How does nanoFlowcell drive work in an electric vehicle? Similar to a petrol-driven car, the electrolyte solution is consumed in a nanoFlowcell-powered electric vehicle. Inside the nanoFlowcell (the actual flow cell) one positively and one negatively charged electrolyte solution is pumped past the cell membrane. A reaction - an ion exchange - takes place between the positively and negatively charged electrolyte solutions. The chemical energy contained in bi-ION is thus released as electricity, which is then used to drive the electric motors. This happens for as long as electrolytes are pumped past the membrane and react. In the case of the nanoFlowcell-driven QUANTiNO, one tank of electrolyte liquid is sufficient for more than 1,000 kilometres. Once empty, the tank must be refilled.

What are the "waste products" generated by a nanoFlowcell-driven electric vehicle? In a conventional vehicle with an internal combustion engine, the combustion of fossil fuels (petrol or diesel) produces dangerous exhaust gases - mainly carbon dioxide, nitrogen oxides and sulphur dioxide - the accumulation of which has been identified by many researchers as the cause of climate change. However, the only emissions released by a nanoFlowcell vehicle while driving consist - much like a hydrogen-powered vehicle - almost entirely of water.

After the ion exchange has taken place in the nanoFlowcell, the chemical composition of the bi-ION electrolyte solution remains virtually unchanged. It is no longer reactive and is thus considered "spent" as it cannot be recharged. For mobile applications of nanoFlowcell technology such as electric vehicles, the decision was therefore taken to microscopically vaporise and release the consumed electrolyte solution while the vehicle is running. At speeds upwards of 80 km/h, the holding tank for the consumed electrolyte liquid is emptied via extremely fine spray nozzles using a generator driven by the drive energy. The electrolytes and salts are filtered out mechanically beforehand. The release of the now cleanly filtered water as cold water vapour (micro-fine mist) is entirely environmentally compatible. The filter is changed at roughly 10,000 kilometre intervals, with its subsequent disposal being just as environmentally compatible.

The benefit of this technical solution is that the vehicle tank empties while driving in the usual manner and can be refilled conveniently and quickly without having to be pumped out first.

An alternative solution that is insignificantly more complex would be to collect the spent electrolyte solution in a separate tank and send it for recycling. This solution is envisaged for the likes of stationary nanoFlowcell applications.

Cooling tower

Now, however, many critics are suggesting that water vapour of the type released by hydrogen conversion in fuel cells or through vaporisation of electrolyte liquid in the case of the nanoFlowcell, is theoretically a greenhouse gas that can possibly have an impact on climate change. How do such rumours arise?

We consider water vapour emissions in respect of their environmental relevance and ask the question how much more water vapour might be expected as a result of the widespread use of nanoFlowcell-driven vehicles compared with conventional drive technologies and whether these H2O emissions can have a negative environmental impact.

The most important natural greenhouse gases - alongside CH4, O3 and N2O are water vapour and CO2. Carbon dioxide and water vapour are incredibly important to maintaining the global climate. Solar radiation that reaches the ground is absorbed and heats up the earth, which in turn radiates heat into the atmosphere. However, a large proportion of this radiated heat escapes back into space from the earth's atmosphere. Carbon dioxide and water vapour have the properties of greenhouse gases, forming a "protective layer" that prevents all of the radiated heat from escaping back into space. Within the natural context, this greenhouse effect is critical to our survival on earth - without carbon dioxide and water vapour, the earth's atmosphere would be hostile to life.

The greenhouse effect only becomes problematic when the unpredicted intervention of human beings disturbs the natural cycle. When, in addition to naturally occurring greenhouse gases, human beings cause a higher concentration of greenhouse gases in the atmosphere by burning fossil fuels this magnifies the heating of the earth's atmosphere.


As part of the biosphere, human beings inevitably impact their environment, and therefore the climate system, by their very existence. The continual increase in the global population since the Stone Age and the establishment of settlements several thousand years ago, with the associated transition from nomadic life to agriculture and livestock breeding has already influenced the climate. Almost half of the world's original woodlands and forests have been cleared for agricultural purposes. (>) Forests are - alongside the oceans - a main producer of water vapour.

Water vapour is the main absorber of heat radiation within the atmosphere. Water vapour constitutes an average of 0.3% by mass of the atmosphere, carbon dioxide only 0.038%, meaning that water vapour makes up 80% of the mass of greenhouse gases in the atmosphere (approx. 90% by volume) and, with a contribution of between 36 and 66%, is the most important greenhouse gas securing our existence on earth. (>

Table 3: Atmospheric share of the most important greenhouse gases as well as absolute and relative share of temperature increase (Zittel)
* Source: UNFCCC (>)

Next to naturally occurring water vapour, the greatest anthropogenic - manmade - water vapour emissions are generated by artificial irrigation (IPCC). (>) However, widespread deforestation significantly reduces the release of water vapour that would have an effect many times greater.

The anthropogenic contribution of water vapour is not taken into account in climate model calculations because, compared with natural emissions through evaporation, this represents a share of just 0.005%, making it irrelevant. This contrasts with anthropogenic carbon-dioxide emissions, which, at a share of 4%, are on a scale that has a significant influence on the natural cycle. (>

It also has to be said that the CO2 contribution generated by road traffic worldwide stands at an average of around 11%. What would change if more vehicles emitted water vapour than CO2?


The following estimates have been made in respect of the absolute amount of water vapour emissions in Germany:

Based on average annual precipitation of around 780 mm and a surface area of approx. 360,000 km2, the volume of precipitation stands at around 280 billion tonnes. Natural water vapour emissions per km2 and year are around 0.35 x 106 tonnes. Based on entire surface area, this equates to around 125,000 x 106 tonnes of water vapour per year. This was calculated on the assumption that approx. 50% of the overall precipitation evaporates, with the remaining 50% flowing into the sea via ground and surface water.

If all 45.1 million passenger cars registered in Germany were converted to nanoFlowcell drive, the average mileage would amount to around 1,000 litres of electrolyte per vehicle being vaporised each year, emitting roughly 0.01% of the water vapour arising naturally in Germany. From a global perspective, the enormous quantities of natural evaporation - especially from oceans and forests - make the total anthropogenic proportion of water vapour absolutely negligible (less than 0.005%).


Furthermore, the greenhouse gas effect of water vapour is dependent primarily on its concentration in the various atmospheric layers. The further removed from the surface of the earth, the stronger the greenhouse gas effect produced. Scientists agree that the greenhouse gas potential of anthropogenic water vapour close to the ground should be considered negligible. Water vapour in the stratosphere, on the other hand, where it is emitted by aircraft, represents a hidden additional greenhouse gas potential. (>

We assert that QUANTiNO and QUANT FE are not free of emissions - they still generate water as a "waste product" (as well as small quantities of recyclable electrolyte and salts), but even if all vehicles worldwide were converted to nanoFlowcell drive, the resulting water vapour emissions would have no climate-changing influence. They would produce less water vapour than the amount produced by the forests cut down year after year.

As an environmentally compatible and sustainable energy source, nanoFlowcell will make a positive contribution to the global climate. Every nanoFlowcell-driven electric vehicle that replaces a conventional vehicle with an internal combustion engine contributes to lowering the rise in concentration of carbon oxides, nitrogen oxides and sulphur dioxide.